Rotary boiler hand-hole seat scraper



Jan., 24, 1950 o. F. Hol-:LZEL 2,495,256

ROTARY BoILER HAND-Hom; SEAT sRAPER Filed July 19, 1946 Patented Jan. 24, 1950 ROTARY BOILER HAND-HOLE SEAT SCRAPER Omar F. Hoelzel, Portsmouth, Va.

Application July 19, 1946, Serial No. 684,904

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 O. G. 757) 4 Claims.

This invention relates to a rotary power-driven scraper. In particular, the invention relates to a power-driven rotary scraper which is hollow and frusto-conical in shape.

The general object of the invention is to provide a rotary, power-driven scraper which is adapted to clean the contact surfaces of closures such as the hand-hole seat in the headers of boilers.

It is also an object of this invention to provide a rotary, metallic, power-driven scraper which is composed of metal softer than that of the handhole seat whereby there is no scoring action on the seat by the operation of the scraper.

It is an additional object of this invention to provide a scraper which will remove all foreign material such as rust, and compacted water sediment from the seat, thereby leaving no humps of rust or sediment which cause the hand-hole cover to be cocked when dogged into position and have a deleterious effect on the gasket.

It is a further object of this invention to provide a rotary, power-driven scraper, which is frusto-conical in shape and which constitutes an ecient scraping tool for the removal of foreign material from the seats of hand hole covers in boilers and headers.

t is a still further object of this invention to provide a rotary power driven scraper which is readily manipulated and which is of sturdy construction and capable of economical manufacture.

These and other objects of the invention will appear more fully from the following description, the herewith appended claims and in the accompanying drawing in which,

Figure lis a top elevational view of the scraper,

Figure 2 is a side elevational view of the same,

Figure 3 is a vertical sectional view taken along section line 3-3 of Figure 2. It is partly in section and partly in elevation, and n Figure 4 is a sectional, elevational view showing the scraper of this invention in operative position on the hand-hole seat in a boiler header.

Figures 1, 2 and 3 are self-explanatory. They are submitted for clarity of disclosure.

In Figure 4 the scraper and driving assembly is shown generally at III in operative relationship to handhole seat I2 which is positioned in boiler header I4. The lower edge I6 of scraper II is the scraping and cutting edge which by rotary and rm contact with the handhole seat removes the foreign matter such as rust and compacted water sediment from the seat. Scraper II is frustoconical in shape. Itis hollow, being open at the larger end and closed by integral plate I8 at its smaller end. Plate I8 is provided with a centrally positioned opening I9 through which a threaded portion 20 of shaft 2| projects. This threaded portion 20 is of smaller diameter than shaft 2l, thereby providing a shoulder 22 on the said shaft which functions as an abutment against which washer 24 rests. In assembling the scraper on the driving shaft 2| as herein shown, Washer 2-4 is placed on shoulder 22, scraper II is then positioned with plate I8 resting on washer 24, washer 26 is then immediately placed beyond plate I I and the whole assembly is held rmly in position by nut 28. Shaft 2I extends beyond scraping edge I6 and may be driven by any suitable source of power such as a portable air driven motor 3U.

In use, the rotary scraper is manipulated by grasping the portable motor 30 and directing the scraping edge I6 against hand-hole seat I2 in boiler header I4 and working the scraper II and portable motor 3|] around the hand-hole seat I2 as a unit, holding the scraper edge IE firmly in interior corner I3. In this manner the foreign matter on the seat is quickly and thoroughly removed. It will be obvious that the softer material of the conical body will be worn away by rubbing contact with the harder metal of the surface being cleaned, and that the base of the conical scraper is thereby continually renewed and the edge thereof sharpened as the scraper walls are shortened by wear. The foreign material removed is primarily of material softer than the scraper material, which may be of alloy copper, brass, soft steel, or the like, such that the foreign material is cut thereby. It is preferred that the corneal base of the scraper be approximately tangent to the surface being cleaned in order that the included angle between the base and the cone elements be somewhat less than ninety degrees, as illustrated, since the cleaning action is facilitated by the lifting and shearing action resulting therefrom.

While the foregoing description has been drawn to the application of a rotary, power-driven conically shaped scraper to the cleaning of a boiler header hand-hole seat, it is not desired to be strictly limited thereto, since this type of scraper can be used in cleaning other types of seats and metallic surfaces. Such other applications and uses are included within the scope of the invention to the extent as' defined by the herewith appended claims.

The invention described herein may be manufactured and used by or for the Government of of the metallic surfaces and harder than said,

material, the said body being provided with a closed small end and an open largeend, a portable shaft extending concentrically throughthe,` large end of the body, means for locking the endA of the shaft concentrically to the closed end of the body and means for rotatingth'ebody in confL tact with the surface while the shaft intersects the plane of said surface at substantially ninety degrees thereto, said body; being continuously sharpened at the larger conical ed'geiby said rotation against said surface;

2: Ai rotary, power-driven scraper adapted` to remove foreignlmaterial fromi metallic surfaces comprisingahollow, frusta-conically shaped body composed-of. metal softer than that of the metal,- lic surfaces and provided with asmall end and an` openv large' end; a shaft' extending through the largev end of the body, means-for securingfthe shaft concentricallyfto the-bodyv and means for rotating; the shaftV and bodywith the-conical-base of 'thebody intsubstantiallyfflat engagement with saidsurfaces, the periphera-lxconical'edge thereof. being, a rotative cutting edge; said. rotation continually sharpening-,said edgeby rubbing con-.- tact with said surfaces.v

3; A; rotary, power-driven, scraper adapted to remove foreign,` material fromy metallic surfaces comprising a hollow thin-walled, conical body composed'o softer meta-l Athan-that` of the metal- -lic'surfaces and. provided-with;:ad small end and an openlargeend-having aperipheral-edge, a Alo shaft extending concentrically through the body to the small end thereof, means for securing the shaft to the body and means for rotating the shaft and body with said peripheral edge in scraping contact with the metallic surfaces, said scraping contact continually renewing the peripheral edge of.. the body,v as thethirrwall thereof wears away.

4. A rotary, power-driven scraper adapted to remove foreign material from metallic surfaces comprising a thin-walled, tapered hollow body composed ofmetal softer than that of the metallie surfaces, the said body being provided with a closedsmall end and an open large end, the largest diameter thereof forming a circular cutting edge, a portableshaft extending through the large end of the body, means for locking the end of thev shaft to the closed end of the body and means for: holding androtating the portable shaft and body with; saidopen large end in substantially flat scraping contact with said surfaces, said scraping contact. continually sharpening said edge.v

OMAR. F. HOELZEL.

REFERENCES CITED The following references are of record in the le-of' this patent:

UNITED STATES" PATENTS Number Name Date 460,312 Schweizer Sept. 29, 1891 1,140,047 Lewis May 18, 1915 1,584,481 Skuttle MayV 11, 1926 1,616,007 Smith Feb. 1, 1927 1,917,383 McCarthy July l1, 1933 2,280,149 Gerst: Apr. 21, 1942 2,299,089 Haan Oct. 20, 1942 FOREIGNT PATENTS Number Country Date 609,172l GermanyA Feb. 8, 1935 

